Commit Graph

150 Commits

Author SHA1 Message Date
Daniel P. Berrangé
b5b89e9bc6 util: don't set SO_REUSEADDR on client sockets
Setting the SO_REUSEADDR property on a socket allows binding to a port
number that is in the TIMED_WAIT state. This is usually done on listener
sockets, to enable a server to restart itself without having to wait for
the completion of TIMED_WAIT on the port.

It is also possible, but highly unusual, to set it on client sockets. It
is rare to explicitly bind() a client socket, since it is almost always
fine to allow the kernel to auto-bind a client socket to a random free
port. Most systems will have many 10's of 1000's of free ports that
client sockets will be bound to.

eg on Linux

  $ sysctl -a | grep local_port
  net.ipv4.ip_local_port_range = 32768	60999

eg on OpenBSD

  $ sysctl -a | grep net.inet.ip.port
  net.inet.ip.portfirst=1024
  net.inet.ip.portlast=49151
  net.inet.ip.porthifirst=49152
  net.inet.ip.porthilast=65535

A connected socket must have a unique set of value for

 (protocol, localip, localport, remoteip, remoteport)

otherwise it is liable to get EADDRINUSE.

A client connection should trivially avoid EADDRINUSE if letting the
kernel auto-assign the 'localport' value, which QEMU always does.

When QEMU sets SO_REUSEADDR on a client socket on OpenBSD, however, it
upsets this situation.

The OpenBSD kernel appears to happily pick a 'localport' that is in the
TIMED_WAIT state, even if there are many other available local ports
available for use that are not in the TIMED_WAIT state.

A test program that just loops opening client sockets will start seeing
EADDRINUSE on OpenBSD when as few as 2000 ports are in TIMED_WAIT,
despite 10's of 1000's ports still being unused. This contrasts with
Linux which appears to avoid picking local ports in TIMED_WAIT state.

This problem on OpenBSD exhibits itself periodically with the migration
test failing with a message like[1]:

  qemu-system-ppc64: Failed to connect to '127.0.0.1:24109': Address already in use

While I have not been able to reproduce the OpenBSD failure in my own
testing, given the scope of what QEMU tests do, it is entirely possible
that there could be a lot of ports in TIMED_WAIT state when the
migration test runs.

Removing SO_REUSEADDR from the client sockets should not affect normal
QEMU usage, and should improve reliability on OpenBSD.

This use of SO_REUSEADDR on client sockets is highly unusual, and
appears to have been present since the very start of the QEMU socket
helpers in 2008. The orignal commit has no comment about the use of
SO_REUSEADDR on the client, so is most likely just an 16 year old
copy+paste bug.

[1] https://lists.nongnu.org/archive/html/qemu-devel/2024-10/msg03427.html
    https://lists.nongnu.org/archive/html/qemu-devel/2024-02/msg01572.html

Fixes: d247d25f18
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2024-10-22 11:44:23 +01:00
Dr. David Alan Gilbert
a347207514 sockets: Remove deadcode
socket_remote_address hasn't been used since it was added in
  17c55decec ("sockets: add helpers for creating SocketAddress from a socket")

inet_connect hasn't been used since 2017's
  8ecc2f9eab ("sheepdog: Use SocketAddress and socket_connect()")

Remove them.

Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2024-10-22 11:44:23 +01:00
Markus Armbruster
4edb196e20 qapi: Improve documentation of file descriptor socket addresses
SocketAddress branch @fd is documented in enum SocketAddressType,
unlike the other branches.  That's because the branch's type is String
from common.json.

Use a local copy of String, so we can put the documentation in the
usual place.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240205074709.3613229-14-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2024-02-12 10:04:32 +01:00
Michael Tokarev
d02d06f8f1 util: spelling fixes
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20230823065335.1919380-3-mjt@tls.msk.ru>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2023-08-31 19:47:43 +02:00
Eric Blake
bd1386cce1 cutils: Adjust signature of parse_uint[_full]
It's already confusing that we have two very similar functions for
wrapping the parse of a 64-bit unsigned value, differing mainly on
whether they permit leading '-'.  Adjust the signature of parse_uint()
and parse_uint_full() to be like all of qemu_strto*(): put the result
parameter last, use the same types (uint64_t and unsigned long long
have the same width, but are not always the same type), and mark
endptr const (this latter change only affects the rare caller of
parse_uint).  Adjust all callers in the tree.

While at it, note that since cutils.c already includes:

    QEMU_BUILD_BUG_ON(sizeof(int64_t) != sizeof(long long));

we are guaranteed that the result of parse_uint* cannot exceed
UINT64_MAX (or the build would have failed), so we can drop
pre-existing dead comparisons in opts-visitor.c that were never false.

Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20230522190441.64278-8-eblake@redhat.com>
[eblake: Drop dead code spotted by Markus]
Signed-off-by: Eric Blake <eblake@redhat.com>
2023-06-02 12:27:19 -05:00
Marc-André Lureau
25657fc6c1 win32: replace closesocket() with close() wrapper
Use a close() wrapper instead, so that we don't need to worry about
closesocket() vs close() anymore, let's hope.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Message-Id: <20230221124802.4103554-17-marcandre.lureau@redhat.com>
2023-03-13 15:39:31 +04:00
Markus Armbruster
f560eb1f0a sockets: Use ERRP_GUARD() where obviously appropriate
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221121085054.683122-9-armbru@redhat.com>
2022-12-14 16:19:35 +01:00
Stefan Hajnoczi
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Merge tag 'net-pull-request' of https://github.com/jasowang/qemu into staging

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# gpg: Signature made Fri 28 Oct 2022 01:29:25 EDT
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* tag 'net-pull-request' of https://github.com/jasowang/qemu: (26 commits)
  net: stream: add QAPI events to report connection state
  net: stream: move to QIO to enable additional parameters
  qemu-sockets: update socket_uri() and socket_parse() to be consistent
  qemu-sockets: move and rename SocketAddress_to_str()
  net: dgram: add unix socket
  net: dgram: move mcast specific code from net_socket_fd_init_dgram()
  net: dgram: make dgram_dst generic
  net: stream: add unix socket
  net: stream: Don't ignore EINVAL on netdev socket connection
  net: socket: Don't ignore EINVAL on netdev socket connection
  qapi: net: add stream and dgram netdevs
  net: introduce qemu_set_info_str() function
  qapi: net: introduce a way to bypass qemu_opts_parse_noisily()
  net: simplify net_client_parse() error management
  net: remove the @errp argument of net_client_inits()
  net: introduce convert_host_port()
  vhost: Accept event idx flag
  vhost: use avail event idx on vhost_svq_kick
  vhost: toggle device callbacks using used event idx
  vhost: allocate event_idx fields on vring
  ...

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-10-30 18:30:01 -04:00
Laurent Vivier
7651b32119 qemu-sockets: update socket_uri() and socket_parse() to be consistent
To be consistent with socket_uri(), add 'tcp:' prefix for inet type in
socket_parse(), by default socket_parse() use tcp when no prefix is
provided (format is host:port).

In socket_uri(), use 'vsock:' prefix for vsock type rather than 'tcp:'
because it makes a vsock address look like an inet address with CID
misinterpreted as host.
Goes back to commit 9aca82ba31 "migration: Create socket-address parameter"

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2022-10-28 13:28:52 +08:00
Laurent Vivier
18bf1c9456 qemu-sockets: move and rename SocketAddress_to_str()
Rename SocketAddress_to_str() to socket_uri() and move it to
util/qemu-sockets.c close to socket_parse().

socket_uri() generates a string from a SocketAddress while
socket_parse() generates a SocketAddress from a string.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2022-10-28 13:28:52 +08:00
Bin Meng
926a895c2c util/qemu-sockets: Use g_get_tmp_dir() to get the directory for temporary files
Replace the existing logic to get the directory for temporary files
with g_get_tmp_dir(), which works for win32 too.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2022-10-26 13:32:08 +01:00
Bin Meng
d409373b9d util/qemu-sockets: Enable unix socket support on Windows
Support for the unix socket has existed both in BSD and Linux for the
longest time, but not on Windows. Since Windows 10 build 17063 [1],
the native support for the unix socket has come to Windows. Starting
this build, two Win32 processes can use the AF_UNIX address family
over Winsock API to communicate with each other.

[1] https://devblogs.microsoft.com/commandline/af_unix-comes-to-windows/

Signed-off-by: Xuzhou Cheng <xuzhou.cheng@windriver.com>
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220802075200.907360-3-bmeng.cn@gmail.com>
2022-09-02 15:54:46 +04:00
Bin Meng
e3fdb13e88 util/qemu-sockets: Replace the call to close a socket with closesocket()
close() is a *nix function. It works on any file descriptor, and
sockets in *nix are an example of a file descriptor.

closesocket() is a Windows-specific function, which works only
specifically with sockets. Sockets on Windows do not use *nix-style
file descriptors, and socket() returns a handle to a kernel object
instead, so it must be closed with closesocket().

In QEMU there is already a logic to handle such platform difference
in os-posix.h and os-win32.h, that:

  * closesocket maps to close on POSIX
  * closesocket maps to a wrapper that calls the real closesocket()
    on Windows

Replace the call to close a socket with closesocket() instead.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2022-08-05 16:18:15 +01:00
Marc-André Lureau
0f9668e0c1 Remove qemu-common.h include from most units
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220323155743.1585078-33-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-06 14:31:55 +02:00
Marc-André Lureau
e7b7942822 Drop qemu_foo() socket API wrapper
The socket API wrappers were initially introduced in commit
00aa0040 ("Wrap recv to avoid warnings"), but made redundant with
commit a2d96af4 ("osdep: add wrappers for socket functions") which fixes
the win32 declarations and thus removed the earlier warnings.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2022-03-22 14:40:51 +04:00
Marc-André Lureau
653163fcbc build-sys: add HAVE_IPPROTO_MPTCP
The QAPI schema shouldn't rely on C system headers #define, but on
configure-time project #define, so we can express the build condition in
a C-independent way.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20210907121943.3498701-3-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-09-30 15:30:25 +02:00
Markus Armbruster
935a867c87 qapi: Convert simple union SocketAddressLegacy to flat one
Simple unions predate flat unions.  Having both complicates the QAPI
schema language and the QAPI generator.  We haven't been using simple
unions in new code for a long time, because they are less flexible and
somewhat awkward on the wire.

To prepare for their removal, convert simple union SocketAddressLegacy
to an equivalent flat one, with existing enum SocketAddressType
replacing implicit enum type SocketAddressLegacyKind.  Adds some
boilerplate to the schema, which is a bit ugly, but a lot easier to
maintain than the simple union feature.

Cc: "Daniel P. Berrangé" <berrange@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210917143134.412106-9-armbru@redhat.com>
2021-09-27 08:23:25 +02:00
Michael Tokarev
118d527f2e qemu-sockets: fix unix socket path copy (again)
Commit 4cfd970ec1 added an
assert which ensures the path within an address of a unix
socket returned from the kernel is at least one byte and
does not exceed sun_path buffer. Both of this constraints
are wrong:

A unix socket can be unnamed, in this case the path is
completely empty (not even \0)

And some implementations (notable linux) can add extra
trailing byte (\0) _after_ the sun_path buffer if we
passed buffer larger than it (and we do).

So remove the assertion (since it causes real-life breakage)
but at the same time fix the usage of sun_path. Namely,
we should not access sun_path[0] if kernel did not return
it at all (this is the case for unnamed sockets),
and use the returned salen when copyig actual path as an
upper constraint for the amount of bytes to copy - this
will ensure we wont exceed the information provided by
the kernel, regardless whenever there is a trailing \0
or not. This also helps with unnamed sockets.

Note the case of abstract socket, the sun_path is actually
a blob and can contain \0 characters, - it should not be
passed to g_strndup and the like, it should be accessed by
memcpy-like functions.

Fixes: 4cfd970ec1
Fixes: http://bugs.debian.org/993145
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
CC: qemu-stable@nongnu.org
2021-09-06 17:18:54 +03:00
Marc-André Lureau
4cfd970ec1 util: fix abstract socket path copy
Commit 776b97d360 "qemu-sockets: add abstract UNIX domain socket
support" neglected to update socket_sockaddr_to_address_unix() and
copied the whole sun_path without taking "salen" into account.

Later, commit 3b14b4ec49 "sockets: Fix socket_sockaddr_to_address_unix()
for abstract sockets" handled the abstract UNIX path, by stripping the
leading \0 character and fixing address details, but didn't use salen
either.

Not taking "salen" into account may result in incorrect "path" being
returned in monitors commands, as we read past the address which is not
necessarily \0-terminated.

Fixes: 776b97d360
Fixes: 3b14b4ec49
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: xiaoqiang zhao <zxq_yx_007@163.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2021-08-04 23:23:31 +04:00
Vladimir Sementsov-Ogievskiy
c542370418 qemu-sockets: introduce socket_address_parse_named_fd()
Add function that transforms named fd inside SocketAddress structure
into number representation. This way it may be then used in a context
where current monitor is not available.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210610100802.5888-6-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: comment tweak]
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-06-18 10:59:53 -05:00
Dr. David Alan Gilbert
8bd1078aeb sockets: Support multipath TCP
Multipath TCP allows combining multiple interfaces/routes into a single
socket, with very little work for the user/admin.

It's enabled by 'mptcp' on most socket addresses:

   ./qemu-system-x86_64 -nographic -incoming tcp:0:4444,mptcp

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210421112834.107651-6-dgilbert@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-06-08 19:36:22 +01:00
Stefan Hajnoczi
37179e9ea4 sockets: update SOCKET_ADDRESS_TYPE_FD listen(2) backlog
socket_get_fd() fails with the error "socket_get_fd: too many
connections" if the given listen backlog value is not 1.

Not all callers set the backlog to 1. For example, commit
582d4210eb ("qemu-nbd: Use SOMAXCONN for
socket listen() backlog") uses SOMAXCONN. This will always fail with in
socket_get_fd().

This patch calls listen(2) on the fd to update the backlog value. The
socket may already be in the listen state. I have tested that this works
on Linux 5.10 and macOS Catalina.

As a bonus this allows us to detect when the fd cannot listen. Now we'll
be able to catch unbound or connected fds in socket_listen().

Drop the num argument from socket_get_fd() since this function is also
called by socket_connect() where a listen backlog value does not make
sense.

Fixes: e5b6353cf2 ("socket: Add backlog parameter to socket_listen")
Reported-by: Richard W.M. Jones <rjones@redhat.com>
Cc: Juan Quintela <quintela@redhat.com>
Cc: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20210310173004.420190-1-stefanha@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-05-11 12:43:26 -05:00
Markus Armbruster
8acefc79de sockets: Make abstract UnixSocketAddress depend on CONFIG_LINUX
The abstract socket namespace is a non-portable Linux extension.  An
attempt to use it elsewhere should fail with ENOENT (the abstract
address looks like a "" pathname, which does not resolve).  We report
this failure like

    Failed to connect socket abc: No such file or directory

Tolerable, although ENOTSUP would be better.

However, introspection lies: it has @abstract regardless of host
support.  Easy enough to fix: since Linux provides them since 2.2,
'if': 'defined(CONFIG_LINUX)' should do.

The above failure becomes

    Parameter 'backend.data.addr.data.abstract' is unexpected

I consider this an improvement.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-11-03 13:17:25 +00:00
Markus Armbruster
ef298e3826 sockets: Bypass "replace empty @path" for abstract unix sockets
unix_listen_saddr() replaces empty @path by unique value.  It obtains
the value by creating and deleting a unique temporary file with
mkstemp().  This is racy, as the comment explains.  It's also entirely
undocumented as far as I can tell.  Goes back to commit d247d25f18
"sockets: helper functions for qemu (Gerd Hoffman)", v0.10.0.

Since abstract socket addresses have no connection with filesystem
pathnames, making them up with mkstemp() seems inappropriate.  Bypass
the replacement of empty @path.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-11-03 13:17:12 +00:00
Markus Armbruster
3b14b4ec49 sockets: Fix socket_sockaddr_to_address_unix() for abstract sockets
Commit 776b97d360 "qemu-sockets: add abstract UNIX domain socket
support" neglected to update socket_sockaddr_to_address_unix().  The
function returns a non-abstract socket address for abstract
sockets (wrong) with a null @path (also wrong; a non-optional QAPI str
member must never be null).

The null @path is due to confused code going back all the way to
commit 17c55decec "sockets: add helpers for creating SocketAddress
from a socket".

Add the required special case, and simplify the confused code.

Fixes: 776b97d360
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-11-03 13:09:41 +00:00
Markus Armbruster
b08cc97d6b sockets: Fix default of UnixSocketAddress member @tight
An optional bool member of a QAPI struct can be false, true, or absent.
The previous commit demonstrated that socket_listen() and
socket_connect() are broken for absent @tight, and indeed QMP chardev-
add also defaults absent member @tight to false instead of true.

In C, QAPI members are represented by two fields, has_MEMBER and MEMBER.
We have:

            has_MEMBER    MEMBER
    false         true     false
    true          true      true
    absent       false  false/ignore

When has_MEMBER is false, MEMBER should be set to false on write, and
ignored on read.

For QMP, the QAPI visitors handle absent @tight by setting both
@has_tight and @tight to false.  unix_listen_saddr() and
unix_connect_saddr() however use @tight only, disregarding @has_tight.
This is wrong and means that absent @tight defaults to false whereas it
should default to true.

The same is true for @has_abstract, though @abstract defaults to
false and therefore has the same behavior for all of QMP, HMP and CLI.
Fix unix_listen_saddr() and unix_connect_saddr() to check
@has_abstract/@has_tight, and to default absent @tight to true.

However, this is only half of the story.  HMP chardev-add and CLI
-chardev so far correctly defaulted @tight to true, but defaults to
false again with the above fix for HMP and CLI.  In fact, the "tight"
and "abstract" options now break completely.

Digging deeper, we find that qemu_chr_parse_socket() also ignores
@has_tight, leaving it false when it sets @tight.  That is also wrong,
but the two wrongs cancelled out.  Fix qemu_chr_parse_socket() to set
@has_tight and @has_abstract; writing testcases for HMP and CLI is left
for another day.

Fixes: 776b97d360
Reported-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-11-03 13:09:28 +00:00
Daniel P. Berrangé
dfc00eb7de util: include the target address in socket connect failures
Reporting "Failed to connect socket" is essentially useless for a user
attempting to diagnose failure. It needs to include the target address
details. Similarly when failing to create a socket we should include the
socket family info, so the user understands what particular feature was
missing in their kernel build (IPv6, VSock in particular).

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-10-29 09:57:37 +00:00
Kevin Wolf
947e47448d monitor: Use getter/setter functions for cur_mon
cur_mon really needs to be coroutine-local as soon as we move monitor
command handlers to coroutines and let them yield. As a first step, just
remove all direct accesses to cur_mon so that we can implement this in
the getter function later.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20201005155855.256490-4-kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2020-10-09 07:08:19 +02:00
Stefan Hajnoczi
d73415a315 qemu/atomic.h: rename atomic_ to qatomic_
clang's C11 atomic_fetch_*() functions only take a C11 atomic type
pointer argument. QEMU uses direct types (int, etc) and this causes a
compiler error when a QEMU code calls these functions in a source file
that also included <stdatomic.h> via a system header file:

  $ CC=clang CXX=clang++ ./configure ... && make
  ../util/async.c:79:17: error: address argument to atomic operation must be a pointer to _Atomic type ('unsigned int *' invalid)

Avoid using atomic_*() names in QEMU's atomic.h since that namespace is
used by <stdatomic.h>. Prefix QEMU's APIs with 'q' so that atomic.h
and <stdatomic.h> can co-exist. I checked /usr/include on my machine and
searched GitHub for existing "qatomic_" users but there seem to be none.

This patch was generated using:

  $ git grep -h -o '\<atomic\(64\)\?_[a-z0-9_]\+' include/qemu/atomic.h | \
    sort -u >/tmp/changed_identifiers
  $ for identifier in $(</tmp/changed_identifiers); do
        sed -i "s%\<$identifier\>%q$identifier%g" \
            $(git grep -I -l "\<$identifier\>")
    done

I manually fixed line-wrap issues and misaligned rST tables.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200923105646.47864-1-stefanha@redhat.com>
2020-09-23 16:07:44 +01:00
zhaolichang
8cc360b93a util/: fix some comment spelling errors
I found that there are many spelling errors in the comments of qemu,
so I used the spellcheck tool to check the spelling errors
and finally found some spelling errors in the util folder.

Signed-off-by: zhaolichang <zhaolichang@huawei.com>
Reviewed-by: Alex Bennee <alex.bennee@linaro.org>
Message-Id: <20200917075029.313-6-zhaolichang@huawei.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2020-09-17 20:38:42 +02:00
xiaoqiang zhao
776b97d360 qemu-sockets: add abstract UNIX domain socket support
unix_listen/connect_saddr now support abstract address types

two aditional BOOL switches are introduced:
tight: whether to set @addrlen to the minimal string length,
       or the maximum sun_path length. default is TRUE
abstract: whether we use abstract address. default is FALSE

cli example:
-monitor unix:/tmp/unix.socket,abstract,tight=off
OR
-chardev socket,path=/tmp/unix.socket,id=unix1,abstract,tight=on

Signed-off-by: xiaoqiang zhao <zxq_yx_007@163.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-05-20 10:34:40 +01:00
Simran Singhal
b3ac2b94cd Compress lines for immediate return
Compress two lines into a single line if immediate return statement is found.

It also remove variables progress, val, data, ret and sock
as they are no longer needed.

Remove space between function "mixer_load" and '(' to fix the
checkpatch.pl error:-
ERROR: space prohibited between function name and open parenthesis '('

Done using following coccinelle script:
@@
local idexpression ret;
expression e;
@@

-ret =
+return
     e;
-return ret;

Signed-off-by: Simran Singhal <singhalsimran0@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200401165314.GA3213@simran-Inspiron-5558>
[lv: in handle_aiocb_write_zeroes_unmap() move "int ret" inside the #ifdef]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2020-05-04 14:43:22 +02:00
Vladimir Sementsov-Ogievskiy
da5e116918 util/qemu-sockets: fix keep_alive handling in inet_connect_saddr
In "if (saddr->keep_alive) {" we may already be on error path, with
invalid sock < 0. Fix it by returning error earlier.

Reported-by: Coverity (CID 1405300)
Fixes: aec21d3175
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20190910075943.12977-1-vsementsov@virtuozzo.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2019-09-25 08:15:44 -05:00
Juan Quintela
e5b6353cf2 socket: Add backlog parameter to socket_listen
Current parameter was always one.  We continue with that value for now
in all callers.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
---
Moved trace to socket_listen
2019-09-03 23:24:42 +02:00
Vladimir Sementsov-Ogievskiy
aec21d3175 qapi: Add InetSocketAddress member keep-alive
It's needed to provide keepalive for nbd client to track server
availability.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20190725094937.32454-1-vsementsov@virtuozzo.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Daniel P. Berrangé <berrange@redhat.com>
[eblake: Fix error message typo]
Signed-off-by: Eric Blake <eblake@redhat.com>
2019-08-15 13:22:13 -05:00
Markus Armbruster
a8d2532645 Include qemu-common.h exactly where needed
No header includes qemu-common.h after this commit, as prescribed by
qemu-common.h's file comment.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-5-armbru@redhat.com>
[Rebased with conflicts resolved automatically, except for
include/hw/arm/xlnx-zynqmp.h hw/arm/nrf51_soc.c hw/arm/msf2-soc.c
block/qcow2-refcount.c block/qcow2-cluster.c block/qcow2-cache.c
target/arm/cpu.h target/lm32/cpu.h target/m68k/cpu.h target/mips/cpu.h
target/moxie/cpu.h target/nios2/cpu.h target/openrisc/cpu.h
target/riscv/cpu.h target/tilegx/cpu.h target/tricore/cpu.h
target/unicore32/cpu.h target/xtensa/cpu.h; bsd-user/main.c and
net/tap-bsd.c fixed up]
2019-06-12 13:20:20 +02:00
Marc-André Lureau
caf88d74a7 util: simplify unix_listen()
The only caller of unix_listen() left is qga/channel-posix.c.

There is no need to deal with legacy coma-trailing options ",...".

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20190503130034.24916-6-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-05-10 14:54:11 +02:00
Daniel P. Berrangé
2d2023c3b9 sockets: avoid string truncation warnings when copying UNIX path
In file included from /usr/include/string.h:494,
                 from include/qemu/osdep.h:101,
                 from util/qemu-sockets.c:18:
In function ‘strncpy’,
    inlined from ‘unix_connect_saddr.isra.0’ at util/qemu-sockets.c:925:5:
/usr/include/bits/string_fortified.h:106:10: warning: ‘__builtin_strncpy’ specified bound 108 equals destination size [-Wstringop-truncation]
  106 |   return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In function ‘strncpy’,
    inlined from ‘unix_listen_saddr.isra.0’ at util/qemu-sockets.c:880:5:
/usr/include/bits/string_fortified.h:106:10: warning: ‘__builtin_strncpy’ specified bound 108 equals destination size [-Wstringop-truncation]
  106 |   return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We are already validating the UNIX socket path length earlier in
the functions. If we save this string length when we first check
it, then we can simply use memcpy instead of strcpy later, avoiding
the gcc truncation warnings.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20190501145052.12579-1-berrange@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2019-05-03 13:03:04 +02:00
Paolo Bonzini
7d37435bd5 avoid TABs in files that only contain a few
Most files that have TABs only contain a handful of them.  Change
them to spaces so that we don't confuse people.

disas, standard-headers, linux-headers and libdecnumber are imported
from other projects and probably should be exempted from the check.
Outside those, after this patch the following files still contain both
8-space and TAB sequences at the beginning of the line.  Many of them
have a majority of TABs, or were initially committed with all tabs.

    bsd-user/i386/target_syscall.h
    bsd-user/x86_64/target_syscall.h
    crypto/aes.c
    hw/audio/fmopl.c
    hw/audio/fmopl.h
    hw/block/tc58128.c
    hw/display/cirrus_vga.c
    hw/display/xenfb.c
    hw/dma/etraxfs_dma.c
    hw/intc/sh_intc.c
    hw/misc/mst_fpga.c
    hw/net/pcnet.c
    hw/sh4/sh7750.c
    hw/timer/m48t59.c
    hw/timer/sh_timer.c
    include/crypto/aes.h
    include/disas/bfd.h
    include/hw/sh4/sh.h
    libdecnumber/decNumber.c
    linux-headers/asm-generic/unistd.h
    linux-headers/linux/kvm.h
    linux-user/alpha/target_syscall.h
    linux-user/arm/nwfpe/double_cpdo.c
    linux-user/arm/nwfpe/fpa11_cpdt.c
    linux-user/arm/nwfpe/fpa11_cprt.c
    linux-user/arm/nwfpe/fpa11.h
    linux-user/flat.h
    linux-user/flatload.c
    linux-user/i386/target_syscall.h
    linux-user/ppc/target_syscall.h
    linux-user/sparc/target_syscall.h
    linux-user/syscall.c
    linux-user/syscall_defs.h
    linux-user/x86_64/target_syscall.h
    slirp/cksum.c
    slirp/if.c
    slirp/ip.h
    slirp/ip_icmp.c
    slirp/ip_icmp.h
    slirp/ip_input.c
    slirp/ip_output.c
    slirp/mbuf.c
    slirp/misc.c
    slirp/sbuf.c
    slirp/socket.c
    slirp/socket.h
    slirp/tcp_input.c
    slirp/tcpip.h
    slirp/tcp_output.c
    slirp/tcp_subr.c
    slirp/tcp_timer.c
    slirp/tftp.c
    slirp/udp.c
    slirp/udp.h
    target/cris/cpu.h
    target/cris/mmu.c
    target/cris/op_helper.c
    target/sh4/helper.c
    target/sh4/op_helper.c
    target/sh4/translate.c
    tcg/sparc/tcg-target.inc.c
    tests/tcg/cris/check_addo.c
    tests/tcg/cris/check_moveq.c
    tests/tcg/cris/check_swap.c
    tests/tcg/multiarch/test-mmap.c
    ui/vnc-enc-hextile-template.h
    ui/vnc-enc-zywrle.h
    util/envlist.c
    util/readline.c

The following have only TABs:

    bsd-user/i386/target_signal.h
    bsd-user/sparc64/target_signal.h
    bsd-user/sparc64/target_syscall.h
    bsd-user/sparc/target_signal.h
    bsd-user/sparc/target_syscall.h
    bsd-user/x86_64/target_signal.h
    crypto/desrfb.c
    hw/audio/intel-hda-defs.h
    hw/core/uboot_image.h
    hw/sh4/sh7750_regnames.c
    hw/sh4/sh7750_regs.h
    include/hw/cris/etraxfs_dma.h
    linux-user/alpha/termbits.h
    linux-user/arm/nwfpe/fpopcode.h
    linux-user/arm/nwfpe/fpsr.h
    linux-user/arm/syscall_nr.h
    linux-user/arm/target_signal.h
    linux-user/cris/target_signal.h
    linux-user/i386/target_signal.h
    linux-user/linux_loop.h
    linux-user/m68k/target_signal.h
    linux-user/microblaze/target_signal.h
    linux-user/mips64/target_signal.h
    linux-user/mips/target_signal.h
    linux-user/mips/target_syscall.h
    linux-user/mips/termbits.h
    linux-user/ppc/target_signal.h
    linux-user/sh4/target_signal.h
    linux-user/sh4/termbits.h
    linux-user/sparc64/target_syscall.h
    linux-user/sparc/target_signal.h
    linux-user/x86_64/target_signal.h
    linux-user/x86_64/termbits.h
    pc-bios/optionrom/optionrom.h
    slirp/mbuf.h
    slirp/misc.h
    slirp/sbuf.h
    slirp/tcp.h
    slirp/tcp_timer.h
    slirp/tcp_var.h
    target/i386/svm.h
    target/sparc/asi.h
    target/xtensa/core-dc232b/xtensa-modules.inc.c
    target/xtensa/core-dc233c/xtensa-modules.inc.c
    target/xtensa/core-de212/core-isa.h
    target/xtensa/core-de212/xtensa-modules.inc.c
    target/xtensa/core-fsf/xtensa-modules.inc.c
    target/xtensa/core-sample_controller/core-isa.h
    target/xtensa/core-sample_controller/xtensa-modules.inc.c
    target/xtensa/core-test_kc705_be/core-isa.h
    target/xtensa/core-test_kc705_be/xtensa-modules.inc.c
    tests/tcg/cris/check_abs.c
    tests/tcg/cris/check_addc.c
    tests/tcg/cris/check_addcm.c
    tests/tcg/cris/check_addoq.c
    tests/tcg/cris/check_bound.c
    tests/tcg/cris/check_ftag.c
    tests/tcg/cris/check_int64.c
    tests/tcg/cris/check_lz.c
    tests/tcg/cris/check_openpf5.c
    tests/tcg/cris/check_sigalrm.c
    tests/tcg/cris/crisutils.h
    tests/tcg/cris/sys.c
    tests/tcg/i386/test-i386-ssse3.c
    ui/vgafont.h

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20181213223737.11793-3-pbonzini@redhat.com>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Eric Blake <eblake@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Stefan Markovic <smarkovic@wavecomp.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-01-11 15:46:56 +01:00
Daniel P. Berrange
1723d6b1cf sockets: allow SocketAddress 'fd' to reference numeric file descriptors
The SocketAddress 'fd' kind accepts the name of a file descriptor passed
to the monitor with the 'getfd' command. This makes it impossible to use
the 'fd' kind in cases where a monitor is not available. This can apply in
handling command line argv at startup, or simply if internal code wants to
use SocketAddress and pass a numeric FD it has acquired from elsewhere.

Fortunately the 'getfd' command mandated that the FD names must not start
with a leading digit. We can thus safely extend semantics of the
SocketAddress 'fd' kind, to allow a purely numeric name to reference an
file descriptor that QEMU already has open. There will be restrictions on
when each kind can be used.

In codepaths where we are handling a monitor command (ie cur_mon != NULL),
we will only support use of named file descriptors as before. Use of FD
numbers is still not permitted for monitor commands.

In codepaths where we are not handling a monitor command (ie cur_mon ==
NULL), we will not support named file descriptors. Instead we can reference
FD numers explicitly. This allows the app spawning QEMU to intentionally
"leak" a pre-opened socket to QEMU and reference that in a SocketAddress
definition, or for code inside QEMU to pass pre-opened FDs around.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2018-03-13 18:06:06 +00:00
Daniel P. Berrange
30bdb3c56d sockets: check that the named file descriptor is a socket
The SocketAddress struct has an "fd" type, which references the name of a
file descriptor passed over the monitor using the "getfd" command. We
currently blindly assume the FD is a socket, which can lead to hard to
diagnose errors later. This adds an explicit check that the FD is actually
a socket to improve the error diagnosis.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2018-03-13 18:06:06 +00:00
Daniel P. Berrange
58dc31f1a7 sockets: move fd_is_socket() into common sockets code
The fd_is_socket() helper method is useful in a few places, so put it in
the common sockets code. Make the code more compact while moving it.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2018-03-13 18:06:06 +00:00
Markus Armbruster
9af2398977 Include less of the generated modular QAPI headers
In my "build everything" tree, a change to the types in
qapi-schema.json triggers a recompile of about 4800 out of 5100
objects.

The previous commit split up qmp-commands.h, qmp-event.h, qmp-visit.h,
qapi-types.h.  Each of these headers still includes all its shards.
Reduce compile time by including just the shards we actually need.

To illustrate the benefits: adding a type to qapi/migration.json now
recompiles some 2300 instead of 4800 objects.  The next commit will
improve it further.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-24-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[eblake: rebase to master]
Signed-off-by: Eric Blake <eblake@redhat.com>
2018-03-02 13:45:50 -06:00
Daniel P. Berrange
3e32370a96 sockets: fix parsing of ipv4/ipv6 opts in parse_socket_addr
The inet_parse() function looks for 'ipv4' and 'ipv6' flags, but only
treats them as bare bool flags. The normal QemuOpts parsing would allow
on/off values to be set too.

This updates inet_parse() so that its handling of the 'ipv4' and 'ipv6'
flags matches that done by QemuOpts.

This impacts the NBD block driver parsing the legacy filename syntax and
the migration code parsing the socket scheme.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <20180125171412.21627-1-berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-02-05 18:09:45 +01:00
Daniel P. Berrange
62473511ec sockets: remove obsolete code that updated listen address
When listening on unix/tcp sockets there was optional code that would update
the original SocketAddress struct with the info about the actual address that
was listened on. Since the conversion of everything to QIOChannelSocket, no
remaining caller made use of this feature. It has been replaced with the ability
to query the listen address after the fact using the function
qio_channel_socket_get_local_address. This is a better model when the input
address can result in listening on multiple distinct sockets.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <20171212111219.32601-1-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-21 09:22:44 +01:00
Philippe Mathieu-Daudé
ff676046fb misc: remove duplicated includes
exec: housekeeping (funny since 02d0e09503)

applied using ./scripts/clean-includes

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2017-12-18 17:07:02 +03:00
Daniel P. Berrange
2d7ad7c05e sockets: avoid crash when cleaning up sockets for an invalid FD
If socket_listen_cleanup is passed an invalid FD, then querying the socket
local address will fail. We must thus be prepared for the returned addr to
be NULL

Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-11-28 10:48:04 +00:00
Daniel P. Berrange
10a7b7e6fd sockets: avoid leak of listen file descriptor
If we iterate over the full port range without successfully binding+listening
on the socket, we'll try the next address, whereupon we overwrite the slisten
file descriptor variable without closing it.

Rather than having two places where we open + close socket FDs on different
iterations of nested for loops, re-arrange the code to always open+close
within the same loop iteration.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-11-07 14:10:20 +00:00
Knut Omang
9cf961bba7 sockets: Handle race condition between binds to the same port
If an offset of ports is specified to the inet_listen_saddr function(),
and two or more processes tries to bind from these ports at the same time,
occasionally more than one process may be able to bind to the same
port. The condition is detected by listen() but too late to avoid a failure.

This function is called by socket_listen() and used
by all socket listening code in QEMU, so all cases where any form of dynamic
port selection is used should be subject to this issue.

Add code to close and re-establish the socket when this
condition is observed, hiding the race condition from the user.

Also clean up some issues with error handling to allow more
accurate reporting of the cause of an error.

This has been developed and tested by means of the
test-listen unit test in the previous commit.
Enable the test for make check now that it passes.

Reviewed-by: Bhavesh Davda <bhavesh.davda@oracle.com>
Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com>
Reviewed-by: Girish Moodalbail <girish.moodalbail@oracle.com>
Signed-off-by: Knut Omang <knut.omang@oracle.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-16 16:55:31 +01:00
Knut Omang
39f80521df sockets: factor out create_fast_reuse_socket
Another refactoring step to prepare for fixing the problem
exposed with the test-listen test in the previous commit

Signed-off-by: Knut Omang <knut.omang@oracle.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2017-10-16 16:55:08 +01:00